Upholsteries of elastic sponge material



Jan 11?, W6? A. CLEMENT! ETAL 3,298,046

UIHOLSTERlES OI ELASTJU SPONGE MATERIAL Filed Nov. 30, 1964 6 Armandofile/wen?! Giorgia Tangarm A ORNEYS INVENTORS United States Patent3,298,046 UPHOLSTEREES 0F ELASTKC SPONGE MATERIAL Armando Clementi andGiorgio Tangorra, Milan, Italy, assignors to Pirelli San-"a S.p.A.,Milan, Italy Filed Nov. 30, 1964, Ser. No. 414,726 Claims priority,application Italy, Dec. 3, 1963, 24,818/63 14 Claims. (Cl. -445) Thepresent invention relates to improvements to up-' holsteries of moldedelastic sponge material for furniture or vehicles.

Elastic sponge upholsteries of different kinds, such as mattresses,cushioins for seats or backs of vehicles and the like, comprising amolded piece substantially consisting of a continuous layer and aplurality of integral blocks, are well known. The blocks are connectedperpendicular to the continuous layer in a direction parallel to that ofthe normally applied load, that is to the height of the upholstery. Theblocks are tapered and have a transverse section (variable resistantsection) Whose area is gradually variable along the load direction. Thegreater and smaller bases of these blocks have the same geometricalconfiguration.

In conventional blocks, the variation of a transverse sec tion throughthe height is such that the lateral face of the block has a lateralprofile quite linear or quite convex towards the outside. Consequentlythe blocks have a shape of truncated pyramids or of truncated cones, oreven of spherical segments.

Upholsteries of this type, comprising a single molded piece (in whichcase an upper layer of material was bonded to the face of the smallerbase of the blocks) or two overturned superposed molded pieces (theblocks of which were in mutual contact) possessed, at the first contactwith the users body or under small loads, a sufiicient softness oryieldingness as well as a fair resistance to compression underconsiderable loads. That is to say that these types of upholsteries metthe requirements essential to ensure satisfactory comfort. In suchupholsteries, the intermediate spaces between the tapered blocksconstituted horizontal channels which cooperated to the obtention of theabove mentioned requirements.

It is therefore an object of the present invention to improve thecharacteristics of comfort of upholsteries of the above indicated type.

Another object of the present invention is to provide an improvedupholstery, of the type comprising tapered blocks, in which each blockhas a greater base of a quadrangular configuration and a smaller base ofpolygonal configuration with a number of sides greater than four, or, asan alternative, a circular configuration, and the lateral surfaceconnecting two adjacent bases is a continuous and outwardly directedconcavity. More precisely, the corn cavity is intended as referring tothe sections defined by the lateral surface at the lines of intersectionwith planes passing through the axis of a block.

The present invention will be more clearly understood from the followingdetailed description, given by way: of non-limiting example and madewith reference to the attached drawings, in which:

FIG. 1 is a top view of a detail of a molded unit provided with blocksaccording to the invention;

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken along line 33 of FIG. 1;

FIG. 4- is a sectional View, analogous to that of FIG. 2, of anupholstery according to one embodiment of the invention;

FIG. 5 is a sectional view, analogous to that of FIG. 2,

of an upholstery according to another embodiment of the invention; and

FIG. 6 is a sectional view of an upholstery according to a furtherembodiment of the invention, taken along a depression between theashlars of the service surface.

Referring now tothe drawings, according to the invention, a molded piecell of elastic sponge material, as for instance sponge rubber or expanded(porous) polyurethane, comprises a continuous layer 2 and a plurality ofintegral equal tapered blocks 3. The blocks are attached adjacent to oneanother to the continuous layer by their greater bases 4. The greaterbase 4, of each block 3, has a quadrangular, preferably squareconfiguration, as illustrated in FIG. 1. The smaller base 5 is concentric with respect to the greater base and has a differentconfiguration, that is a polygonal configuration with a number of sidesgreater than four. This base has been illustrated by a polygon with themaximum number of sides, namely a base of circular configuration.

The lateral surface s, of each block, joins the two bases havingdifferent geometric configurations. This surface is characterized by acontinuous and outwardly directed concave shape. The concavity isreferred to as the 'sec tions defined by the lateral surface at thelines of intersection with planes passing through the axis of the block.

With reference to the molded piece illustrated in FIG. 1, FIG. 2illustrates the concave path of the line obtained by sectioning thelateral surface 6, of each block 3, at the line of intersection with theplane 2-2 passing through the axis of the block and the middle point ofthe concerned sides of the greater base 4. FIG. 3 illustrates theconcave path of the line obtained in the same way as in FIG. 2, onlywith respect to the plane 3-3 passing through the axis of the block andthe ends of the concerned sides of the greater base 4.

From FIG. 2 it may be noted that the sectioning line has a sharplycurved path, in close proximity with the greater base 4- which tapersoff gradualiy to an only slightly curved path near the smaller base.FIG. 3 represents the curved path as having a substantially uniformradius assumed by the sectioning line 6 with respect to the di agonal ofthe greater base 4.

The path of the sectioning lines, which are obtained by starting fromthe middle point of a side of the greater base and moving to either endof that same side, varies gradually from the limit condition indicatedin FIG. 2 to the limit condition indicated in FIG. 3.

The curves represented by the sectioning line, in the limit conditionsillustrated in FIGS. 2 and 3 as well as the corresponding intermediatepositons and in any other embodi ment in accordance with the invention,comprise portions which may be analytically expressed by mathematicalquadratic functions, as parabolas, ellipses, circles and hyperbolas,whose centers of curvature are outside the block.

When the sectioning line lies in the limit condition as shown in FIG. 2,the curved path (of small radius) has, prefer-ably, radius equal to orgreater than of the block height. If desired, the sectioning lines,besides comprising curved portions, may comprise rectilinear segmentsfor connection or completion with the continuous layer. It is preferablethat the area of the greater base exceed that of the smaller base by atleast. 40%. If required, or if preferable, the individual blocks 3 maybe provided with vertical recesses 7 as illustrated.

As shown in FIG. 4-, it is possible to manufacture an upholstery byapplying and securing to a piece, molded in accordance with theinvention, a layer 8 of an elastic sponge material. The layer is securedto the upwardly directed smaller bases of the blocks of the invention.The upper layer 8 is suitably molded or cut and constitutes the servicesurface of the upholstery. In FIG. 4-, the reference numeral 9 indicatesa horizontal channel originated by the tapering of the blocks.

Two molded pieces may be superposed, in an already known way, with therespective smaller bases of the block in mutual contact. This isillustrated in FIG. with pieces 1 and 1'. The reference numeral 10indicates the inner horizontal channels comprised bet-ween theoverturned superposed tapered blocks. Of course, this embodiment wouldbe reversible with either side being the service surface area.

It is understod that two molded pieces may be combined with other piecesin a way different from that indicated above. For instance, in theembodiment illustrated in FIG. 5, single elements of elastic spongematerial, having a density different from that of the materialconstituting the molded pieces, may be interposed between the smallerbases of the overturned oppose-d blocks. Moreover the service surfacesor surfaces of the upholstery may be provided with ashlars, in analready known manner, in such a way that each ashlar may cover thegreater base of the relative block. In this case, in particular, incorrespondence of each crossing of the depressions between the ashlars,the inner horizontal channels, which cross analogously to saiddepressions, decrease in the height, that is at said points the heightof said channels is lower than at other points of the same between twocontiguous crossings. This obviously results in the quadrangularconfiguration of the greater base having curved sides each having anoutwardly directed concavity. This has been illustrated in FIGURE 6,which is a section taken along one of said depressions of a mattressaccording to the invention having a cover over the elastic spongematerial.

In the upholstery obtained, according to the present invention, thefeatures of softness or yieldingness at the first contact with the usersbody or under small loads, and the resistance to compression underconsiderable loads are improved over the conventional upholsteries ofthis type. Furthermore, the invention achieves an economy of materialover the conventional upholsteries.

In other words, the uphlosteries according to the present invention areadvantageously lighter than the conventional upholsteries while theirmechanical properties are improved. Moreover, by virtue of the practicalelimination of any corner edges and of any discontinuity from the lateral surfaces of the blocks, these upholsteries possess an improvedresistance to fatigue stresses. The smaller base of polygonal shape witha number of sides greater than four, and, in the maximum case ofcircular shape, permits a more uniform distribution of the recessesinside each block which contributes to the improvement of the comfortoffered by the upholstery. The expression quadrangular configuration, ashere used, means any polygon (comprising those having curved sides)having four vertices and consequently four angles.

Having thus described the invention, what is claimed and desired to besecured by Letters Patent in the United States is:

1. An upholstery for furniture or vehicles comprising a molded piece ofelastic sponge material consisting of a continuous layer and uniformlytapered blocks, said blocks having a greater base and a smaller basewith a cross sec tion variable from the former to the latter, saidgreater bases being attached to and integral with said continuous layer,said greater base having a quadrangular configuration, said smaller basehaving a closed plane configuration, 65

a lateral surface connecting the two bases and having a continuous andvariable outwardly directed concave conformation, said concavity beingnoted in the sections defined by the lateral surface at lines ofintersection with planes passing through the axis of said block and saidvariability taking place between said sections.

2. An upholstery according to claim 1 wherein said smaller base has acircularconfiguration.

3. An upholstery according to claim 1, wherein said sectioning lines ofsaid lateral surface comprise portions which may be analyticallyexpressed by mathematical quadratic functions.

4. An upholstery according to claim 1 wherein the sectioning lines inclose proximity to the greater base and near a limit condition assume aradius no less than of the height of the block.

5. An upholstery according to claim 1 wherein said blocks are providedwith a plurality of recesses perpendicular to and depending from saidsmaller base.

6. An upholstery according to claim 1 wherein the area of the greaterbase of said block exceeds the area of the smaller base by at least 40%.

7. An upholstery according to claim 1 wherein a layer of elastic spongematerial is disposed across said molded piece, said layer contacting thesmaller bases of said blocks, and said layer forming a service surfaceof said upholstery.

S. An upholstery according to claim 1 wherein two of said molded piecesare disposed in overturned superposed position with their blocksmutually opposed and attached by the smaller bases, and said continuouslayers providing service surfaces.

9. An upholstery according to claim 1 wherein two of said molded piecesare disposed in overturned superposed position with their blocksmutually opposed and attached by the smaller bases, and said continuouslayers providing service surfaces, said surfaces being provided withcrossed depressions, and wherein in correspondence of each crossing ofsaid depressions the height of the inner horizontal channels, whichcross analogously to the depressions, may be lower than at other pointsof the channels between two continuous crossings.

It An upholstery according to claim 9 wherein single elements of elasticsponge material having a density difierent from that of the materialconstituting the two molded pieces are interposed between the mutuallyopposed smaller bases of said molded pieces.

11. An upholstery according to claim 9 wherein said upholstery is amattress.

12. An upholstery according to claim 9 wherein both said servicesurfaces are covered by a suitable wear-resistant decorative material.

13. An upholstery according to claim 9 wherein both said servicesurfaces are covered by a suitable wear-resistant decorative materialand the article thus formed is a mattress.

14. An upholstery according to claim 1 wherein said smaller base has apolygonal configuration with a number of sides greater than four.

References Cited by the Examiner UNITED STATES PATENTS 1,994,234 3/1935Sherover 5345 2,141,271 12/1938 Gerlofson 536l 2,588,823 3/1952 Glassman5345 2,835,313 5/1958 Dodge 5--36l FRANK B. SHERRY, Primary Examiner.

A. M. CALVERT, Assistant Examiner.

1. AN UPHOLSTERY FOR FURNITURE OR VEHICLES COMPRISING A MOLDED PIECE OFELAXTIC SPONGE MATERIAL CONSISTING OF A CONTINUOUS LAYER AND UNIFORMLYTAPERED BLOCKS, SAID BLOCKS HAVING A GREATER BASE AND A SMALLER BASEWITH A CROSS SECTION VARIABLE FROM THE FORMER TO THE LATTER, SAIDGREATER BASES BEING ATTACED TO AND INTEGRAL WITH SAID CONTINUOUS LAYER,SAID GREATER BASE HAVING A QUADRANGULAR CONFIGURATION, SAID SMALLER BASEHAVING A CLOSED PLANE CONFIGURATION, A LATERIAL SURFACE CONNECTING THETWO BASES AND HAVING A CONTINUOUS AND VARIABLE OUTWARDLY DIRECTEDCONCAVE CONFIRMATION, SAID CONCAVITY BEING NOTED IN THE SECTIONS DEFINEDBY THE LATERAL SURFACE AT LINES OF INTERSECTION WITH